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  <title>Document</title>
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  <script>
    var arr = [2, 5, 10,15,  3, 30, 18]

    // 需求 筛选除 大于等于 10的 

    var newArr = []
    // var index = 0

    for(var i = 0; i < arr.length; i++) {
      // if(arr[i] >= 10) {
      //   newArr[index] = arr[i]
      //   index++
      // }

      if(arr[i] >= 10) {
        newArr[newArr.length] = arr[i]
      }
    }

    console.log( newArr )
  </script>
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